Mind Locked
by bttf4444
Summary: Doc invents a telepathic device that malfunctions and causes Marty, Calvin, and Jennifer to have their minds locked together. Will Doc be able to resolve the problem? BackToTheFanFic Challenge
1. Chapter 1

**Disclaimer: I do not own Back to the Future.**

**Author's Notes: This story is written for this month's BackToTheFanfic challenge. This story be will a little longer than my usual monthly challenges - as foxywriter had imposed a larger word limit on this challenge.  
**

_February 2, 1986  
1:30 PM PST_

Doc checked out his telepathic device, to put the finishing touches on it. After having spent the last few weeks finetuning the device - as well as having performed several tests with his sheepdog, Einstein - he figured he was now about ready to test out the device with his three young friends. He had been friends with the McFly twins, Calvin and Marty, since they were almost seven years old. Technically, though, he had first seen Marty during that fateful week in 1955. He was surprised to discover that Marty ended up with a twin brother. After all, he did remember looking at that photograph of Marty with his other brother and sister - but there was no twin in that photograph.

Doc hadn't been close with Marty's girlfriend, Jennifer Parker, for quite as long. As a matter of fact, he was quite reluctant about letting Jennifer in on his secret about the time machine that he had unveiled to Marty and Calvin over three months ago - until Marty's secret regarding his trip to 1955 has threatened his relationship with Jennifer. As he recently had discovered that Marty and Jennifer were destined to be married in the future, he then saw no harm in letting her in on the secret.

Doc sighed, as he remembered that Marty and Jennifer usually ate out for dinner on Saturdays. He decided to give the McFly home a ring - to see if Calvin, at least, was home. Calvin currently was not dating anyone - even though he was, one day, fated to marry and have a son who was the same age and very closely resembled Marty's future son. It was best not to tell Calvin who he was fated to marry, though - as that could be too risky on the space-time continuum.

After the phone had rung about three times, a familiar voice answered, 'Hello, this is the McFly residence! Who am I speaking with?'

'Listen, Calvin, is that you?' asked Doc, as his heart was racing with anticipation.

'Hello, Doc,' replied Calvin. 'Yeah, it's me! Marty and Jennifer had gotten back here about fifteen minutes. So what's up, Doc? What's going on?'

'Well,' explained Doc, 'I was wanting to ask if the three of you would be able to meet in my lab, to test out my new telepathic device. After finetuning that thing for several weeks, I believe I finally have the thing working properly. I have already done a few tests with Einstein - but, because he's a dog, he really can only think visually.'

'Well, I would have no problems with coming over,' replied Calvin. 'It appears that Marty and Jennifer are busy making out with each other, though. I am not sure if I would be able to pull those two lovebirds apart. You know how they can get?'

'Well, I guess there is no real big hurry,' Doc said, quietly. 'Although, I must say that I'm a little anxious to try out my new experiment. At least, tell them that they should make it a point to come over later on this afternoon.'

'Calvin, is that Doc on the phone?' Marty could be heard asking, in the background.

'Hold on just a second, Doc,' Calvin told Doc. Then, in the background, he could be heard saying, 'Yes, Marty, it's Doc. He is calling to let us know that his new science experiment is ready, and he wants us to come over as soon as we can.'

'Tell Doc that we're ready to go now,' replied Marty, with great enthusiasm.

'Well, Doc,' Calvin said, into the phone, 'I guess Marty and Jennifer are both ready to leave now. I guess we'll be over at your place in about fifteen minutes.'

'Oh, good,' Doc said, with relief. 'I'll be waiting for you then. See you a little later!'

'See you, Doc,' replied Calvin, as he hung up the phone.

Doc's heart was skipping wildly, as he waited patiently for his three young friends to arrive. He hoped that the machine would work properly. He had to admit that he felt a pang of jealousy for Marty, as he had longed to have a romantic interest in his life. He decided that it was best to not lose all hope, though.

oooooooooo

Marty was feeling a little nervous, as he was driving over to Doc's lab with Calvin and Jennifer. He knew that, besides the time machine, Doc rarely ever was able to invent something that actually worked. He knew that Doc had been rather excited about his telepathic device - and he had a feeling that, just like with the beloved time machine, Doc would not be able to release this invention to the public.

'Are you feeling all right, Marty?' Calvin asked, with concern. 'I am a little concerned about you. I mean, you seemed to have been a bit tense the past few days.'

'I'm just a bit concerned for Doc,' Marty said, shrugging. 'I remember he had started working on the telepathic device shortly after you returned from that other universe - which I guess is similar to original timeline I grew up in. As a matter of fact, I gather that everything up until my counterpart was shot dead by those Libyans was exactly the same as what happened in the original timeline.'

'So are you feeling a little concerned for your counterpart?' Calvin asked, concerned.

'A little bit, I guess,' admitted Marty. 'I mean, this could have happened to me! As a matter of fact, it did happen to me! It happened to an alternate version of me! Now that we brought him back to life, I wonder if his life as ever be the same. After all, it is a well known fact that he came back from the dead. Everyone will be referring to him as a modern day Lazerus. This just can't be an easy life for him to live.'

'Well, just try not to worry about it so much,' suggested Calvin. 'The last time we saw him, he seemed to be doing just fine. Anyway, it is not as if your life is really all that much easier. I mean, with all this dealing with having two sets of memories.'

'Yeah, I suppose you are right,' Marty said, sighing. 'Well, we are almost there, now. I suppose it must have been from seeing Sabrina again, that it convinced him to start working on that device. Well, I wonder how it will work. I am a little bit nervous.'

'I think it will be interesting, Marty,' Jennifer said, enthusiastically. 'Just think, Marty, you and I will be able to keep in touch - and you won't ever have to worry if anything happens to me, or vice versa. Just think, it'll be so awesome!'

'Jennifer is right,' Calvin said, nodding. 'Although, I'm not so sure how well telepathic communication would work - if one of us was travelling through time. Still, I think it would come in very handy for us.'

'I have to admit that I'm worried that the telepathic device may malfunction,' Marty said, shrugging. 'Even with that mind reader device that he was working on back in 1955, he had only managed to get it working successfully a couple months ago.'

'Remember, though,' Calvin pointed out, 'you did mention that when he used that mind reader device on you in 1955 - he never realized that it was working, albeit erratically. I think Doc does sometimes give up a little too easily.'

Marty sighed a little bit, as he pulled into the Burger King, up to Doc's lab. The trio then stepped out of the car, as they walked up to knock on the door.

'Oh, good,' Doc said, enthusiastically, as he opened up the door. 'You have made it. Well, why don't you all come in - and we'll test out the telepathic device right away.'

Marty, Calvin, and Jennifer had all followed Doc into the back of the lab. Marty had to admit that he was feeling a little jittery. He tried his hardest to keep calm, though, for Doc's sake. He told himself that he could trust Doc, and that there really was nothing to worry about. Anyway, he had already taken a few trips in Doc's time machine.

'Okay, I'm going to set these caps onto your heads,' Doc explained. 'Try your best to clear your mind of all thoughts, then I will tell you what to do next.

Marty took in a deep breath, as he tried his hardest to not think of anything. He just stared ahead, as Doc went to flip on a switch.

'Okay, Marty,' Doc instructed, 'think of a statement, and Jennifer should then repeat it aloud. Do you understand, everyone?'

'Check, Doc,' replied all three teens, as Marty felt a little panicky.

'Now, Marty,' Doc instructed. 'Then, Jennifer, repeat his statement right away.'

_Envision world peace and harmony_, Marty thought, deadpanned.

'Envision world peace and harmony,' Jennifer repeated, smiling.

'I guess this thing really is working!' Marty exclaimed, stunned.

'It works!' Doc exclaimed, skipping around, excitedly. 'This thing actually works!' 


	2. Chapter 2

_February 2, 1986  
2:00 PM PST_

'Good for you, Doc!' Marty said, admiringly.

'Thank you all for coming over to test this out,' Doc said, smiling. He then grabbed a big cap, and explained, 'I'm going to put on this cap and listen to you all telepathically communicate with each other. You won't be able to hear my thoughts, though.'

'Check, Doc,' replied the three teens. Marty was feeling a little jittery.

'Okay, now!' instructed Doc, as he flipped a switch.

_Can you hear me thinking?_ Marty asked, telepathically.

_Is that you, Marty?_ Jennifer asked. _Where would you like to eat tonight?_

_I'm in the mood for Perkin's_, replied Marty. _I really love their beef french dip sandwiches. It's too bad that we can't eat there more often._

_Yeah, the food there can be very expensive_, agreed Calvin. _I can't say that I myself am too much of a beef person, though. I prefer fish and chicken._

_Yeah, I really do enjoy beer battered cod a lot_, commented Marty. _However, I had that last night - so I want something different today._

_So I guess you guys don't mind being Catholic, then_, Jennifer added. _I almost always do opt for breaded cod on Fridays, even though I'm Protestant._

_Well, that part of Lent I really don't mind_, Marty replied. _However, it can really be killer to have to abstain from something during that time._

_Think you can ever abstain from rock and roll?_ Calvin teased.

_No way!_ Marty exclaimed, horrified. _I would go crazy without rock music._

_So I guess you are obsessed with rock and roll_, Calvin remarked, smirking.

_Will you stop saying that, Calvin?_ Marty asked, with a bit of annoyance.

_No, I won't_, Calvin insisted, smirking. _Not until you can admit it!_

_Fine, I'm obsessed_, Marty said, sighing. _Now leave me alone about it!_

_I'm not fooled, Marty_, Calvin replied. _I know you weren't being sincere about admitting it. You only said it just to get to get me to shut up._

_Okay, fine, so I did_, Marty replied, with annoyance. _Is that a crime?_

_Calvin, just leave Marty alone_, instructed Jennifer. _I know you're just playing around, but I really think you can take it way too far._

_Thank you, Jennifer_, Marty replied, with relief. _Calvin, I think this joke is getting really old! You like football, I really don't! We all have our passions!_

Doc then flipped a switch, and commented, 'I might as well just nip this in the bud, before things become real ugly.' Then, turning to Calvin, he sternly said, 'You really should stop bugging your brother about his passion for rock music. I can tell that he is starting to get very annoyed with that.'

'Yeah,' agreed Jennifer, nodding in agreement, 'you two are supposed to be best friends - and you do get along most of the time. Sometimes Marty and I like to tease each other, too - but you really are starting to take this too far.'

'Okay, fine,' Calvin whispered, blushing, 'I'm sorry, Marty. I don't want you to start resenting me. I guess I did carry that joke a little bit too far.'

'Okay, apology is accepted,' Marty said, as he stuck out his hand. 'Can we shake on this, now, buddy?'

'I can do better than that,' Calvin replied, smiling, as he threw his arms around his twin brother to embrace him. 'I really do love you a lot, Marty. You're a great friend!'

'I love you, too, Calvin,' Marty replied, as he hugged his twin back.

_Aw, now isn't that sweet!_ gushed Jennifer.

'What did you say, Jennifer?' Marty asked, as he turned around.

'Huh? I didn't say anything!' Jennifer replied, confused. _Man, I wish I had a twin!_

'I wish you had a twin, too,' replied Calvin. 'Then, that way, all four of us can go on double dates together - and we can maybe even have a double wedding!'

'Calvin, what are you talking about?' Jennifer asked, confused.

'Well, you just said that you wished you had a twin,' Calvin replied. 'Didn't you?'

'No, I didn't say that,' Jennifer replied, stunned. Then, turning to Doc, she asked, 'Are you sure that this telepathic device is turned off?'

'Great Scott!' gasped Doc. 'I thought I turned this thing off!' He went to flip a button, and said, 'All right, let's try this again. Start communicating among yourselves.'

_I really, really, really hate liver!_ Marty thought. _It is very disgusting!_

_I can't stand liver, either_, agreed Jennifer. _Another thing I really cannot stand is squash and sweet potatoes - or baked beans. Baked beans really make me feel like throwing up. I just cannot stomach them._

_I can't believe you and Marty both don't like baked beans_, remarked Calvin. _Well, I guess it just means there's more baked beans for me to enjoy._

_I really hate breakfast sausages, bratwurst. and sauerkraut_, added Marty.

_Oh, well, I love sauerkraut_, Calvin replied. _I can really eat a lot of it._

_I like bratwurst_, added Jennifer, _but not breakfast sausages._

_I don't understand how you two can eat cottage cheese_, Calvin commented, with disgust. _I think it's gross and disgusting! It's made of curdled milk!_

_I guess we all just have our own personal preferences_, Marty said, sighing.

_It's really amazing how the two of you have different tastes in food_, Jennifer commented. _I mean, the two of you are identical twins, after all._

_Yeah, but it doesn't mean that we like all the same things_, replied Marty.

_That's true_, agreed Jennifer. _Still, I always figured that there was something different about taste buds. Like, if you and I switched places, we would also switch tastes in food - although our taste in music, movie, TV shows, and the like would still remain the same. I suppose I could be wrong, though._

'Okay, folks,' commented Doc, 'I'm going to disconnect you guys, now.'

The three teens stood silently, as Doc disconnected the device.

'Okay, lift off your caps and try communicating, now,' instructed Doc.

The three teens tried to communicate with each other, and they shook their heads.

'Well, I guess it worked, then,' Doc said, with relief. 'Now, are you guys going to be sticking around for awhile?'

'I have a huge essay that I'm working on,' explained Calvin. 'I have decided to do my essay on the importance of individuality - and how imposing gender roles and cultural roles on people tend to restrict an individual's freedom of choice.'

'That sounds like an interesting essay, Calvin,' commented Doc. 'I would love to read it after you're finished - if you don't mind.'

'That would be great, Doc,' replied Calvin. Then, turning to Marty, he added, 'I think you'd better start working on your essay, too!'

'Hey, Calvin, I'll be fine,' protested Marty. 'Jennifer and I were planning on taking a walk through Hill Valley Park, before we head over to Perkin's for dinner.'

'I was just trying to be helpful,' Calvin said, shrugging. 'I mean, I really care about you, Marty. I want you to be able to go to college and you can make a decent living. I know that you want to become a rock star - but what if you never get discovered?'

'Will you please stop being so negative, Calvin?' Marty asked, with annoyance.

'Look, Marty,' Calvin said, sighing, 'I am not being negative. I am being realistic. Yes, you are a great guitarist, vocalist, and songwriter - but that doesn't necessarily mean that you'll ever become rich and famous!'

'I think Harmony is a very beautiful song,' gushed Jennifer. 'I mean, who could not like a powerful and insightful song like that?'

'Well, the song sure does have a catchy chorus,' Doc said, laughing. Then, he began to sing, 'Harmony is what we need... To make this world a better place. Harmony is what we need... To bring peace to the human race. Can we ever all live in harmony?'

'Hey, Doc, no offence,' Jennifer said, laughing, 'but I really think you should stick to science. You're singing a bit off-key, you know.'

'Maybe Doc could sing the harmony,' Calvin suggested, laughing, 'while Marty could sing the melody.'

'That's such a great one, Calvin,' Marty said, laughing. 'Although the song is called Harmony, though - it's not intended to be sung in harmony.'

'Aw, you kids don't like my singing?' Doc asked, with a mock wounded expression.

'To be honest,' Marty said, smiling, 'you do much better of your science experiments - than you do at singing.'

'But most of my science experiments fail on me,' protested Doc.

'Not all of them,' Marty said, encouragingly. 'You've got your mind reader device to work a couple months ago - and you've just finished up with your telepathic device. Most importantly, though, you've managed to invent a time machine.'

'I guess that's very true,' Doc said, laughing. 'It's nice that I've actually got the telepathic device to work. Have a good afternoon, now, folks!'

What nobody realized, yet, though - was that Doc's telepathic device ended up working all too well. 


	3. Chapter 3

_February 2, 1986  
4:00 PM PST_

Calvin was sitting at his desk, working on his essay for school, when two strangely familiar voices began to interrupt him.

_Oh, you really love those beef French dip sandwiches_, Jennifer said, laughing. _Don't you, huh, Marty?_

_Well, that is the best food they have at Perkin's_, Marty replied. _It really would be great if there were more restaurants that served those sandwiches._

_I can also tell that you are addicted to the mozzerella cheese sticks_, Jennifer added teasingly. _I swear that you almost live on them!_

_Oh, Jennifer_, Marty said, laughing. _You know that that isn't true!_

_What the hell is going on here?_ Calvin though to himself, perturbed. _Why am I hearing the voices of Marty and Jennifer in my head?_

_Jennifer, are you hearing this?_ Marty asked, stunned. _It sounds like my twin brother that was cutting through my thoughts. Tell me I'm not hallucinating!_

_I don't think you are, either, Marty_, replied Jennifer, gently. _I heard Calvin asking why he was hearing our voices in his head._

_Either the telepathic device that misfired on us_, Calvin though, to himself, _or else I am really starting to go crazy! This is very creepy!_

_Calvin, I think you might need to call Doc_, suggested Marty. _It is definitely his telepathic device! He needs to find a way to fix this!_

_Let's try to disconnect our minds first_, suggested Jennifer. _From what I know about telepathy, most people who have that gift can voluntarily connect or disconnect it by will. Why don't try seeing if that might work, first?_

_Okay_, offered Calvin, _Let's try to concentrate hard, and we can then maybe disconnect our minds. Why don't we all just take a deep breath, and try to clear our minds? We'll see if that maybe works._

_I hope it does work_, Jennifer said, with a sigh. _That last thing I need is to have you and Marty being able to read all my private thoughts._

_All right then_, said Marty. _we can all do this after the count of three! One... two... three..._

Calvin then took a deep breath, hoping that his suggestion worked. He then made an attempt to clear his mind, hoping that he could return to working on his essay.

_Gee, I really hope this worked_, Calvin thought, to himself. _Now let's see where I was. Maybe Marty is right, and I should try to slow down a bit._

_Calvin, is that you?_ Marty's voice was heard asking. _If so, I don't think our plan worked. We may have to call up Doc, and talk to him about this._

_Yeah, I am really worried about this_, agreed Jennifer. _So what are we going to tell Doc? This is really not good for either of us._

_Just leave it to me, Jennifer and Marty_, replied Calvin. _I'll call him and explain to him our predicament. We'll have to just trust Doc on this._

_I'm really not sure that I can_, Jennifer said, with scepticism. _I mean, I have not known him as long as the two of you did. Don't get me wrong. He seems like a very nice person. It's just that most of his inventions seem to not work well._

_Well, Doc is the only one who can disconnect our minds_, Marty reminded her. _Please, Jenn, try not to panic so much. I'm sure he'll work something out._

_I'm going to make the phone call, now_, offered Calvin, as he went to pick up the phone by his bed to call Doc. Fortunately, he was the only one who was home.

'Hello, Dr. Emmett Brown speaking,' Doc said, when he picked up the phone after three rings. 'How may I help you?'

'Oh, good, Doc,' Calvin said, with relief. 'I am so glad you're there. Listen, Doc, it appears that your telepathic device has misfired. Marty, Jennifer, and I cannot seem to disconnect our minds. Even if I'm speaking with you, I am struggling to block their thoughts out of my mind.'

'Great Scott!' Doc gasped, with horror. 'This is worse than I thought! I'll have to go check the circuits on the device - and see what it is that is resulting in this mind lock. It appears that the electric discharge from the telepathic device has somehow caused a disruption of the brain waves of you, Marty, and Jennifer - resulting in a condition of forced telepathy.'

'Doc, English, please,' Calvin pleaded, sighing. 'Remember that I am struggling with trying to block out the thoughts of Marty and Jennifer. It is hard to try to understand what you are saying at the same time.'

'Okay, well, where are you guys right now?' Doc asked, gently.

'Well, I was in my bedroom doing some homework,' explained Calvin, 'and I guess Marty and Jennifer are at Perkin's. I was trying hard to concentrate, when I suddenly heard them talking in my head. At first, I felt I was just going crazy from studying too hard. Then, as we had a little conversation, we found out that it must be the telepathic device. I'll head over to your place right away.'

'Well, don't rush yourselves,' replieded Doc. 'It might take me awhile to see what's wrong with the circuits. Anyway, I think Marty and Jennifer should finish eating. I think I'll just come over to pick you guys up. You really should not be driving under that condition. The last thing I need is for you to have a serious accident.'

'So what do we do, then, Doc?' pleaded Calvin. 'I mean, this is really going to drive us insane. We have to struggle hard to keep back all private thoughts. I mean, Marty is my best friend - and I am entitled to some privacy, as is he. I do like Jennifer, but obviously I'm not in love with her like Marty is.'

'Well, just try to hang tight,' suggested Doc, 'and try to relax as much as you can. It shouldn't not take me over an hour to fix the device.'

'So what do we tell our parents, if they ask why we're distracted?' asked Calvin. 'I mean, it's not like they would believe us about the telepathy.'

'Just tell them that the two of you need to be left alone for awhile,' Doc suggested. 'I mean, knowing your parents, I'm sure they would respect your wishes.'

'Yeah, you're right, Doc,' Calvin said, sighing. 'Well, I suppose I'd better hang up, now - so that you can get to working on a solution.'

'Take good care of yourselves,' replied Doc. 'Just stay where you are, and I'll pick you up when I'm ready.'

'Check, Doc,' replied Calvin. 'Well, see you later!'

_So I guess we just stay at Perkin's until Doc comes to get us_, Jennifer said, sighing. _I suppose we'll just have to keep drinking Tab until they come._

_Whoa, this is heavy_, Marty groaned.

_Yeah, you're telling me_, agreed Calvin, as he went to lie down on his bed. He thought of turning on the radio, but then he figured that the music on the radio may just seep into the mindsof Marty and Jennifer.

oooooooooo

About two hours later, Doc had picked up the three teens to bring them over to his lab. He was finally able to figure out which circuit he needed to tweak, to disconnect the telepathic connection between his three young friends.

'All right,' Doc was saying, 'why don't you put these caps on.'

The three teens had silently followed Doc's instruction.

'If my calculations are correct,' Doc continued, 'when this timer goes off in precisely one minute and 21 seconds, your brain waves will become free of the mind lock - and everything should return to normal.'

The three teens had all taken in a deep breath, as they patiently watched the seconds count down on the timer that Doc had attatched to the telepathic device. As soon as the time hit zero seconds, a soft beep went off.

'All right,' Doc said, with hope, 'see if the three of you are still able to communicate tepathically with each other.'

The three teens had all concentrated, before they all shook their heads and smiled.

'Perfect,' Marty said, smiling. 'I have never felt so relieved in my life before! Well, at least not since I had managed to prevent myself from being erased from existence.'

'Good, I'm glad to hear it,' Doc said, smiling.

'I'm still concerned about one thing,' Calvin said, nervously. 'What if we all end up becoming mind locked again in a few hours?'

'I don't forsee that happening,' Doc replied, confidently. 'Still, maybe it is best to just spend the rest of the night at home - in case it does happen again.'

The three teens all nodded, in agreement.

oooooooooo

Late at night, Marty and Jennifer were both relaxing in Marty's room, as the clock radio was tuned to KKHV. Marty was pondering over how good it felt good to have your brain all to yourself!

'That was some kind of date, wasn't it?' Jennifer asked, laughing.

'Yeah, I would say,' replied Marty grimacing a little. 'I guess you could say that our forced telepathic connection was a little too close for comfort!'

'A _little_?' Jennifer asked, laughing. 'Don't you think that's somewhat of an understatement?'

'Yeah, I guess you're right,' Marty said, as he smiled back. 'Well, at least this didn't last much longer than it did. If it did last longer, it might have done some serious damage to our relationship. I mean, thank goodness that that didn't happen!'

'Well, I think having telepathic abilities can really come in handy, at times,' Jennifer remarked, 'but only if we have the ability to connect or disconnect our telepathic link at will. Maybe, one day, Doc will find a way to give us that gift of telepathy.'

'I do hear what you're saying, Jen,' Marty replied. 'I'm so glad that Doc, at least, found a way to disconnect us from our mind lock. He might need a few more weeks, at least, to tweak the telepathic device to perfection.'

'Well, I really do believe that you and I are destined to marry, someday,' Jennifer said, smiling. 'So Marlene and Marty Jr are our future children.'

'They were, when Calvin and I travelled to the future a few months ago,' Marty replied. 'Doc did say, though, that our future is not written yet. Well, even if we do have the kids at the same time, I will see to it that our son develops the courage to stand up for himself - so that he isn't pushed around by Griff Tannen and the gang.'

'Try not to stress yourself out so much, Marty,' Jennifer said, gently. 'At least you no longer let Needles provoke you into doing exploits when he calls you a chicken.'

'Yeah,' Marty sighed, 'I am way through with caring about what Needles and his ilk think of me. With friends like them, who needs enemies?'

Jennifer just threw her arms around Marty, as the two of them kissed. Marty just had a feeling that he and Jennifer were destined towards a long and fulfilling marriage.


End file.
